• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.149.3-150
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• 2003

CYP3A4 is the most abundant human CYP and oxidizes a diversity of substrates. including various drugs. steroids. and carcinogens. A variety of metal ions are known to affect microsomal monooxygenase activities. Effects of a series of divalent metal ions on the CYP3A4-catalyzed reaction of reconstituted system containing purified CYP3A4. NADPH-P450 reductase (NPR), and cytochrome b5 (b5) were examined. (omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 1998년도 국제심포지움 및 추계학술대회
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• pp.52-52
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• 1998

• Biomolecules & Therapeutics
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• 제20권6호
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• pp.562-568
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• 2012

Cytochrome P450 BM3 (CYP102A1) from Bacillus megaterium is a self-sufficient monooxygenase that consists of a heme domain and FAD/FMN-containing reductase domain (BMR). In this report, the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) by BMR was evaluated as a method for monitoring BMR activity. The electron transfer proceeds from NADPH to BMR and then to BMR substrates, MTT and CTC. MTT and CTC are monotetrazolium salts that form formazans upon reduction. The reduction of MTT and CTC followed classical Michaelis-Menten kinetics ($k_{cat}=4120\;min^{-1}$, $K_m=77{\mu}M$ for MTT and $k_{cat}=6580\;min^{-1}$, $K_m=51{\mu}M$ for CTC). Our continuous assay using MTT and CTC allows the simple, rapid measurement of BMR activity. The BMR was able to metabolize mitomycin C and doxorubicin, which are anticancer drug substrates for CPR, producing the same metabolites as those produced by CPR. Moreover, the BMR was able to interact with CYP1A2 and transfer electrons to promote the oxidation reactions of substrates by CYP1A2 and CYP2E1 in humans. The results of this study suggest the possibility of the utilization of BMR as a surrogate for mammalian CPR.

• Environmental Analysis Health and Toxicology
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• 제8권1_2호
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• pp.1-10
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• 1993

This study was done to determine the toxic effect of fthalide in rats which have oral administration at levels of 100 mg/kg/day for twelve days. It was examined the hematogram and serological parameters, and also the content of cytochrome P-450, the activity of NADPH-cytochrome c reductase, glucose-6-phosphatase, cholinesterase and carboxylesterase in liver. Any significant alteration of hematogram was not found but the value of AST, LDH and content of glucose in serum were statistically increased. The content of cytochrome P-450, the activty of NADPH-cytochrome c reductase were increased but glucose-6-phosphatase were slightly decreased compare with that of control group. The activity of cholinesterase was decreased slightly and on the contrary the activity of carboxylesterase was found to be the tendeny of increase in both of liver and serum.

• 약학회지
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• 제33권1호
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• pp.54-63
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• 1989

Examination of the subacute toxicity of captafol showed that. 1) In the captafol administered group, the body weight was significantly decreased but the amounts of AST, ALT, LDH, BUN, TG in serum were remarkably elevated in comparision to those of the control group. 2) In captafol treated animals, the amount of cytochrome P-450 and the activity of NADPH-cytochrome c reductase in liver and in kidney were decreased, but TAB value in serum and in liver and total ATPase activity in liver and in kideny were found to be remakably elevated. 3) When captafol administered with ethanol to the group, the group showed elevated serum levels of AST, ALT and BUN but the amount of cytochrome P-450 and the activity of NADPH-cytochrome c reductase in liver and in kidney were decreased as the group which was treated with captafol only.

• Archives of Pharmacal Research
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• 제8권3호
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• pp.119-132
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• 1985

The apparent effectiveness of 1-naphthyl-N-methyl carbamate (carbaryl) against a wide variety of insects motivated the study of its mammalian toxicity. In this toxicological study of carbaryl, mature male rats inhaled carbaryl at a mean concentration of 112mg, 168mg and 224 mg/$m^{3}$ for one hour. After inhalation, pentobarbital sleeping time, Nadph-cytochrome c reductase activity, cytochrome p-450 and protein content in liver microsomes, various tissue residues, cholinesterase inhibition in plasma and histopathological findings at autopsy were observed. The pentobarbital sleeping time was prolonged in rats inhaled with carbaryl for one day while the sleeping time was shortened in the 3 days inhaled group. The changes of cytochrome p-450 content and NADPH-cytochrome c reductase activity exhibited biphasic response showing the decrease in the one day inhaled group and the increase in the 3 days inhaled group. The marked depression of plasma ChE activity was observed in rats inhaled with carbaryl at 112 mg/$m^{3}$, however no more progressive effect was observed at the higher concentration of the compound. The main observations in histopathological finding were ciliary detachment, epithelial swelling and subepithelial inflammatory cellular infiltration in trachea due to the irritation.

• Applied Biological Chemistry
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• 제38권2호
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• pp.168-173
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• 1995

Endosulfan이 흰쥐(Balb/c.) 체내의 cytochrome P-450 효소계에 미치는 영향을 조사하기 위해 endosulfan을 7.5 mg/kg 수준으로 복강주사하였다. Endosulfan을 복강주사 처리하여 48시간 후 적출한 흰쥐의 간에서는 cytochrome P-450 함량이 $3.3{\sim}4.2$배, cytochrome $b_5$ 함량이 $2.3{\sim}3.8$배, NADPH cytochrome P-450 reductase 활성이 $5.3{\sim}6.4$배 그리고 총 haem 함량이 $3.1{\sim}3.6$배씩 대조구의 그것들에 비해 증가하였다. Endosulfan은 대조구 흰쥐 간의 cytochrome P-450 효소계와 상호작용하여 파장 387와 389 nm에서 흡광도의 증가를 보였으며 파장 407 nm에서 넓은 흡수대를 형성하였다. 환원형 P-450-CO spectrum은 대조구의 경우 파장 451 nm에서 흡광도의 극대를 보인 반면 endosulfan으로 처리된 흰쥐 간의 그것은 파장 449와 450 nm에서 흡광도의 극대를 보였다. Endosulfan 처리로 흰쥐 간과 신장의 aldrin epoxidase 활성이 각각 2.8배와 2.1배씩 증가하였으며 7-ethoxyresorufin dealkylase 활성은 각각 1.7배와 1.8배씩 증가하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.148.2-149
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• 2003

Recently we have reported that various hydroxystilbenes show strong inhibition of human cytochrome P450 1 enzyme activities. A series of syntheic trans-stilbene derivatives were prepared and their inhibitory potentials were evaluated with the bacterial membrane of recombinant human cytochrome P450 1A1, 1A2 and 1B1 coexpressed with hyman NADPH-P450 reductase to find a new inhibitor of cytochrome P450 enzymes. Of the compounds tested, SY-081 exhibited a potent inhibition of human cytochrome P450 1B1 with an $IC_50$ value of 2.6 nM. (omitted)

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2004년도 춘계학술대회
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• pp.43-48
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• 2004

• 한국독성학회:학술대회논문집
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• 한국독성학회 2004년도 춘계학술대회
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• pp.43-48
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• 2004